The present invention relates generally to heat exchangers. More particularly, it relates to a heat exchanger which has a plurality of tubes having tube ends which extend through at least through one base plate and are sealed by corresponding seals.
Heat exchangers of the above mentioned general type are known in the art. In the known heat exchanger the oval tube ends are connected by expansions of the oval to another oval with the base plate. The base plates in the region of their passages are provided with collars projecting to one side and increasing the abutment surface. This however has the disadvantage that the base plates have a relatively low bending strength. It is also required to select the material thickness of the base plate relatively great, and this increases the weight of the heat exchanger as a whole. For increasing the bending strength steel is utilized as a material for the base plate, naturally it must be provided with a corrosion protective layer. This causes recycling problems, and the material are very expensive.
Another disadvantage of such heat exchanger is that the transition region between the expanded oval tube ends and the remaining tube region is vulnerable since transverse forces cannot be taken efficiently in the transition region. During mounting it is necessary to take measures to avoid certain damage to the heat exchanger.